Ferroli F04 Fault Code (i25 / i29)

Safety disclaimer

Fault code summary

Manufacturer

Ferroli

Fault code

F04

Fault type

PCB/electronics

Severity

temporary

Reset

Ferroli states that F faults reset automatically when the value returns to the normal range.

Applicable models

Ferroli i25, Ferroli i29

Quick answer

Card parameter fault.

What does this fault code mean?

Card parameter fault.

Common causes

• Wrong card parameter setting.

Symptoms

• The display flashes F04; Ferroli classifies F faults as temporary shutdowns.

What can the homeowner safely check?

• Record the code and contact the installer.

Boiler reset information

Ferroli states that F faults reset automatically when the value returns to the normal range.

When should I call an engineer?

Contact a suitably qualified heating engineer when the fault persists, the boiler locks out, or the manufacturer instructions do not resolve it. For gas appliance work in the UK, use a Gas Safe registered engineer.

Engineer diagnosis

• Verify the control-card parameters.

Applicable boiler models

• Ferroli i25
• Ferroli i29

Related fault codes

• A01 — i25 / i29

  No burner ignition.

  Read fault code
• A02 — i25 / i29

  Flame-present signal with the burner off.

  Read fault code
• A03 — i25 / i29

  Overtemperature protection intervention.

  Read fault code
• A06 — i25 / i29

  No flame after the ignition phase.

  Read fault code
• A09 — i25 / i29

  Gas-valve fault.

  Read fault code
• A15 — i25 / i29

  Air-pressure-switch fault F05 generated five times in the last 24 hours.

  Read fault code
• A16 — i25 / i29

  Gas-valve fault.

  Read fault code
• A23 — i25 / i29

  Card parameter fault.

  Read fault code

Manufacturer documentation

Table 9: F04 — Card parameter fault; possible cause wrong card parameter setting.

Last verified

2026-09-12

Frequently asked questions